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1. Subcutaneous injection of the kappa-opioid agonists U50,488 (10 mg kg-1) and tifluadom (3.5 mg kg-1) into Inactin-anaesthetized, saline-infused rats was associated with a diuresis, antinatriuresis and antikaliuresis which lasted for up to 2 h. A high (5 mg kg-1), but not low (0.1 mg kg-1), dose of naloxone blocked the renal effects of U50,488. 2. U50,488 administration in anaesthetized, vasopressin-deficient Brattleboro DI rats was associated with an attenuated diuresis, though the antinatriuretic response remained intact. 3. The diuretic action of U50,488 was associated with an increase in glomerular filtration rate while fractional fluid reabsorption remained steady. In contrast, fractional sodium and potassium reabsorption were increased. 4. These data suggest that kappa-opioid agonists alter renal handling of both water and electrolytes. This appears to be mediated by two separate mechanisms: increased fluid loss largely reflects altered glomerular events while the fall in electrolyte excretion results from altered tubular handling.  相似文献   
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To determine the potential effect of screening on referral patterns, an adult population sample (4,404 men, 5,164 women, 20-69 years of age) was systematically recruited and screened for hypercholesterolemia and then analyzed by different cholesterol referral recommendations. Using levels suggested by the Lipid Research Clinics Coronary Primary Prevention Trial (greater than or equal to 265 mg/dL), 7.3% of men and 5.8% of women would be referred for follow-up. With the suggested recommendations of the National Cholesterol Education Program (NCEP), (greater than or equal to 200 mg/dL), 49.2% of men and 40.2% of women would be referred. The use of age-related definitions of the NIH Consensus Conference on Lipid Lowering results in 28.0% referrals in men and 21.8% in women. From this population, hypercholesterolemia subjects (greater than or equal to 265 mg/dL at screening; n = 624) were invited for a second cholesterol determination (58% returned), which found 36% below the 265 mg/dL level. Population screening for cholesterol is likely to produce large numbers of patients for follow-up, with the actual numbers strongly dependent on cutoff levels and age-sex distributions. Referral and follow-up of these patients may place a significant load on an unprepared health care community.  相似文献   
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BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo.  相似文献   
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Bilateral ulnar agenesis is a rare abnormality. A total of 36 cases are analyzed: 35 of these are documented in the literature and 1 stillborn male is presented in this study. Most patients had one of the three conditions: Al-Awadi/Raas-Rothschild syndrome, syndrome of ulnar aplasia with split hand/split foot deformity, or the Brachmann—de Lange syndrome. Fifty percent of all cases with bilateral ulnar agenesis were associated with lower limb defects and these cases, for the most part, also belonged to the aforementioned syndromes. Nonskeletal, internal organ malformations were identified in 34% of all patients. Nine patients presented with isolated bilateral ulnar agenesis. The Al-Awadi/Raas-Rothschild syndrome and the split hand/split foot deformity are heritable disorders. There was no evidence for genetic etiology in most of the other cases. Bilateral ulnar agenesis in our fetus was part of the Brachmann—de Lange syndrome with associated cardiac defect, diaphragmatic hernia, and umbilical artery agenesis.  相似文献   
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One method used to control costs in community cardiovascular disease surveillance is to limit the number of electrocardiograms (ECGs) used to validate acute myocardial infarction (AMI). The Minnesota Heart Survey investigated the impact of decreasing the maximum number of ECGs analyzed on classification of ECG pattern and final AMI diagnosis (definite, probable, none). A 50% sample of all 1980 acute CHD hospital discharge records (ICD-9 code 410 or 411) from 30 of 31 Twin Cities hospitals were abstracted. Comparing results using all available ECGs in the record (maximum of 12) with those obtained using up to 4 ECGs showed little differences in the ECG classification or final AMI diagnosis.  相似文献   
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